1. Field of the Invention
The present invention concerns a process for the preparation of 1,3-diaminopentane by hydrogenation of 3-aminopentanenitrile in the presence of a Raney.RTM. cobalt catalyst. More specifically, but not by way of limitation, the present invention relates to the selective production of 1,3 diaminopentane by use of a Raney.RTM. cobalt catalyst in the presence of an aqueous caustic solution.
2. Description of Related Art
U.S. Pat. No. 4,211,725 discloses in example 7, the use of Raney.RTM. nickel for the reduction of 3-aminopentanenitrile to 1,3-diaminopentane in 76% yield.
U.S. Pat. No. 4,885,391 discloses the use of Raney.RTM. cobalt which is promoted with chromium as a catalyst for the hydrogenation of C.sub.4 to C.sub.12 nitrites. In this patent, catalyst activity is maintained by the addition of water.
The known process for hydrogenation of 3-aminopentanenitrile with Raney.RTM. nickel has a problem in that it produces by-products 1-methyl and 1-ethyl-3-ethylhexahydropyrimidines and 1,3-diaminopentane dimer high boilers.